The non-pressurized design is built from aluminum and is equipped with Pratt & Whitney Canada PT6A engines and fixed landing gear.

The 19,000-pound (8,600 kg) MTOW airplane can cruise up to 210 knots (390 km/h; 240 mph), with a range of 386 nautical miles (715 km; 444 mi) with 19 passengers.

The Model 408 was launched on November 28, 2017, by Textron Aviation, with an introduction planned for 2020, as a FAR Part 23 type certified design.

[12] FedEx initially planned to take monthly deliveries over four years starting in 2020, and a similar pace for a second batch, if it agrees to that option.

[13] A full-scale mockup of the 19-passenger cabin was displayed at the October 2018 National Business Aviation Association convention.

[1] The second prototype, which first flew in August 2020, was the first production-conforming aircraft and was used for testing the engines, propellers, environmental controls and avionics.

[22] Federal Aviation Administration type certification was granted on March 11, 2022,[24][25] after 2,100 hours of flight tests.

[31] The first 19-seat passenger variant was delivered in April 2023 for use by Western Aircraft, Inc. doing business in Hawaii as Lāna’i Air.

[5][6] The airframe consists of traditional aluminum materials and is equipped with proven Pratt & Whitney Canada PT6A-65 engines, fixed landing gear and Garmin G1000 avionics.